1 целых 2/3 + 5/6 = 2,5
1*3+2/3 + 5/6
5/3 + 5/6
5/3*2 + 5/6*1
10/6 + 5/6
15/6 = 2 целых 3/6 = 2 целых 1/2 = 2,5
